Prophetic Commentary on the Qur'an (Tafseer of the Prophet (pbuh))
Bukhari :: Book 6 :: Volume 60 :: Hadith 165
Narrated Abu Huraira:
Allah's Apostle said, "It was said to the children of Israel, 'Enter the gate in prostration and say Hitatun. (7.161) We shall forgive you, your faults.' But they changed (Allah's Order) and entered, dragging themselves on their buttocks and said, 'Habatun (a grain) in a Sha'ratin (hair)."